Fluid storage and dispensing vessels having colorimetrically verifiable leak-tightness, and method of making same

ABSTRACT

A fluid storage and dispensing vessel having associated therewith a colorimetric member that is effective to change color in exposure to leakage of a gas contained in the vessel. The colorimetric member may be constituted by a film, e.g., of a shrink-wrap character, that contains or is otherwise associated with a colorimetric agent undergoing color change in exposure to fluid leaking from the vessel. Such shrink-wrap film may be applied to a portion of the vessel susceptible to leakage, or alternatively to the entire vessel, so that the film is colorimetrically effective to indicate the occurrence of a leakage event by visually perceptible change of color.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation under 35 USC 120 of U.S. patent application Ser.No. 10/699,863 filed Nov. 3, 2003 and issued on Aug. 7, 2007 as U.S.Pat. No. 7,253,002, in the names of Paul J. Marganski, et al. for “FLUIDSTORAGE AND DISPENSING VESSELS HAVING COLORIMETRICALLY VERIFIABLELEAK-TIGHTNESS, AND METHOD OF MAKING SAME.” The disclosure of said U.S.patent application No. 7,253,002 is hereby incorporated herein byreference in its entirety, for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to fluid storage and dispensing vesselssuch as are utilized for storage, transport and dispensing of reagentgases in semiconductor manufacturing operations. More specifically, theinvention relates to fluid storage and dispensing vessels that arecolorimetrically verifiable as to the occurrence of leakage event(s) inthe vessel history, as well as to a method of making vessels of suchtype.

2. Description of the Related Art

Fluid vessels of widely varying types are extensively utilized inchemical industries, including semiconductor manufacturing, where liquidcontainers, gas cylinders and other types of fluid packages are used tosupply reagents such as hydrides, halides, organometallic gaseouscompounds, etc. to semiconductor manufacturing tools.

In the field of semiconductor manufacturing, new packaging approacheshave been developed in recent years, including low pressureadsorbent-based fluid storage and dispensing vessels of the typedisclosed in Tom et al. U.S. Pat. No. 5,518,528, as commerciallyavailable from ATMI, Inc. (Danbury, Conn.) under the trademark “SDS,”and pressure-regulated fluid storage and dispensing vessels of the typedescribed in Wang et al. U.S. Pat. No. 6,101,816, Wang et al. U.S. Pat.No. 6,089,027 and Wang et al. U.S. Pat. No. 6,343,476, as commerciallyavailable from ATMI, Inc. (Danbury, Conn.) under the trademark “VAC.”Regardless of the specific type of fluid storage and dispensing vesselemployed in a given fluid-consuming operation, it is necessary tomaintain complete structural integrity in the storage, transport anddeployment of such vessels, so that no leakage of contained fluid takesplace, such as by leakage through couplings, valve head fittings, burstdisks or other pressure relief devices associated with the vessel,seams, ports or other joints where welds or bonding media may fail andresult in gas release from the vessel, etc.

The foregoing considerations are particularly acute where the containedfluid is very expensive, as in the microelectronics industry, wherechemical reagents must be in many cases >99.999% pure in order toachieve reliability and acceptability of the product integratedcircuitry that is manufactured using such chemical reagents. Theforegoing also applies where the contained fluid is toxic or hazardousin character, and leakage may compromise human health and safety, orotherwise produce injury or adverse impact on the environment, or to theprocess facility in which the fluid is to be utilized.

For these reasons, it is common practice in the field of industrialfluid containment to subject fluid storage and dispensing vessels toleak-testing procedures, e.g., at the time that they are filled with thefluid and sealed to provide the product package of fluid for subsequentuse.

Although such point-of-origin testing of the leak-tightness of the fluidstorage and dispensing vessel may be effective to detect so-called“leakers,” which then can be isolated and reworked or otherwiseappropriately processed, there remains the potential during subsequenttransport, storage and installation, for damage to occur to the vessel,that may compromise its structural integrity and leak-tightness.

For example, conventional gas cylinders are typically transported inbulk arrays that are strapped or secured together for transportation bytruck, railcar, etc. In this condition, the vessels are subjected toshock, vibration, and impact, during their transport any interveningstorage and final installation. Additionally, differential thermaleffects may be significant, such as where such gas cylinders aretransported by truck or railcar in long-haul operations, during whichvariations of temperature and humidity may adversely affect thestructural integrity of the vessel and mediate leakage of fluid from thecompromised vessel.

The foregoing potential for leakage is ameliorated to some extent bylow-pressure packaging and dispensing of fluids, such as in theaforementioned SDS® and VAC® vessels, but nonetheless remains asignificant risk in the transport, storage and installation of suchvessels. It would therefore be a substantial advance in the art tomarkedly increase the safety characteristics of fluid storage anddispensing vessels, with respect to the occurrence of fluid leakageevents.

SUMMARY OF THE INVENTION

The present invention relates to fluid storage and dispensing systems,such as are utilized to store, transport and deliver industrial gasesand liquids. More specifically, the present invention relates to suchsystems, including apparatus and methods for visually detecting theoccurrence of fluid leakage from a fluid storage and dispensing vessel.

In one aspect, the present invention relates to a fluid storage anddispensing apparatus, comprising a fluid storage and dispensing vesselhaving associated therewith a colorimetric member effective in exposureto fluid leaking from the vessel to change color, thereby providing avisually perceptible response to a leakage event.

In another aspect, the present invention relates to a method of visuallydetecting a leakage event associated with a fluid storage and dispensingvessel, said method comprising disposing in fluid leakage detectionproximity to the vessel a colorimetric member effective to undergo colorchange in exposure to leaking fluid from the vessel.

Additional aspects, features and embodiments of the invention will bemore fully apparent from the ensuing disclosure and appended claims.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation view of a gas cylinder with colorimetricleak-indication elements, according to one embodiment of the invention.

FIG. 2 is a front elevation view of a fluid storage and dispensingvessel shrink-wrapped in a colorimetric film, according to anotherembodiment of the invention.

FIG. 3 is a front sectional elevation view of a fluid storage anddispensing vessel according to yet another embodiment of the invention,wherein the valve head and neck area of the vessel are shrink-wrappedwith a colorimetric indicating film, according to a further embodimentof the invention.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS THEREOF

The present invention is based on the use of a colorimetric indicatingmedium associated with a fluid storage and dispensing vessel, which isdeployed in close proximity to and as an integral structural componentof the vessel assembly, to provide a visually perceptible indication ofthe occurrence of a fluid leakage event, e.g., as may be attributable tovessel rupture, valve head leakage, deterioration of a burst disk orother pressure relief device, or other material failure or componentfailure that produces an undesired release of gas from the vessel.

In one embodiment, the invention utilizes a colorimetric member at aportion of the fluid storage and dispensing vessel that is potentiallysusceptible to fluid leakage, so that the color change incident toundesired fluid release is visually discernable at a glance or byroutine visual inspection. For example, the colorimetric member maycomprise a web or sheet-form material, such as paper, cardboard, fiberboard, felt, non-woven or woven materials, films, polymeric sheet stockor the like, which is impregnated with or otherwise includes acolorimetric agent that in exposure to the fluid contained in the vessel(upon leakage thereof) undergoes a color change to indicate the egressof fluid and the occurrence of an undesired leakage event.

For example, such colorimetric article may be disposed in proximity tothe valve head of a pressurized fluid cylinder, on the valve headitself, or within a valve head cap or other “head” structure of thevessel, to provide a visually perceptible color indication of whether ornot leakage has occurred from the vessel.

In another embodiment, the fluid storage and dispensing vessel is atleast partially shrouded in a colorimetric film material, such as aheat-shrinkable wrap material impregnated with or otherwise including acolorimetric agent that undergoes color change in exposure to the fluidspecies of interest, as deriving from the bulk volume of fluid containedin the vessel.

In another embodiment, the colorimetric heat-shrinkable wrap film isapplied over the head portion of a fluid storage and dispensing vessel,e.g., over the valve head and neck/shoulder region of the vessel.

In yet another embodiment, the colorimetric heat-shrink film is employedto completely wrap the vessel, so as to provide a fully shrouded vesselin which the shrink-wrap film enveloping the vessel provides asupplemental containment structure for the vessel, so that any leakagethat occurs is contained within the shrink-wrap film envelope overlyingthe vessel, while at the same time the heat-shrink wrap film undergoes acolorimetric change upon contact with the leaking gas, to visuallyindicate that a leakage event has occurred.

The heat-shrink wrap film utilized for such purpose may be of anysuitable type. Useful heat shrink film materials include polyvinylchlorides (PVC), polyethylene, polypropylene, polyester,polyethylene/polypropylene copolymers, etc. The heat-shrink filmmaterials may contain additives conferring heat-shrink character to thematerial. Such additives include plasticizers, which under heatingconditions cause contraction of the film to conform same to the shapeand surface(s) of an article on which the film is overlaid.

Polyethylene heat-shrink film is relatively inexpensive, and has athickness that is typically on the order of 1.0 mil and higher.Polyolefin films are commercially available in differing compositionsand multi-layer forms, with such films being readily modifiable withinthe skill of the art to provide suitable tearing resistance, zipperingcontrol, shrink control and other appropriate properties for the shrinkwrap application. PVC heat-shrink films include heat-shrink films havingvery low shrink force characteristics, which are amenable tohigh-throughput manufacturing.

The foregoing heat-shrink films may be applied to the fluid supply anddispensing vessel with conventional shrink wrap machines, includingL-sealers and shrink tunnels, shrink wrap systems with heat guns, traysealing machines, continuous band sealers, vacuum sealers, and the like,as utilized in heat-shrink operations involving food, consumer products,and the like.

The choice of a specific shrink wrap material will be determined by theheat-shrink equipment desired to be employed, as well as the cost,strength, shrink force, shrink temperature, heat-shrink dwell times (atthe shrink temperature), etc.

The heat shrink film utilized in the practice of the present inventionis preferably clear or translucent in character, in order to facilitateobservation of the underlying fluid storage and dispensing vessel (e.g.,to verify absence of damage, maintenance of mechanical integrity, etc.),but the film alternatively may be of an opaque character, so long as thecolorimetric change incident to gas leakage is readily visuallyperceptible by an observer.

Heat-shrink wrap materials usefully employed in the broad practice ofthe present invention thus include the aforementioned polyethylene, PVC,polyolefin, and copolymer films, as well as the film materials disclosedin U.S. Pat. No. 4,786,561 (“Heat-Shrinkable Polymeric Barrier Film”),U.S. Pat. No. 4,690,865 (“Heat-Shrinkable Barrier Film”), U.S. Pat. No.6,342,281 (“Heat-Shrinkable Polyester Films”) and U.S. Pat. No.6,495,224 (“Functionally Enhanced Protective Shrink-Wrap Coverings andMethods for their Manufacture and Use”).

In accordance with a preferred aspect of the invention, the heat-shrinkfilm is impregnated with or otherwise includes a colorimetric agent thatin exposure to the fluid species contained in the vessel undergoes acolor change to evidence the undesired leakage. For such purpose, theheat-shrink film may be coated with the colorimetric agent on aninterior or fluid-contacting side of the film (as opposed to the outer,ambient environment-contacting side of the film), or the colorimetricagent may be formulated in or blended with the film material during itsformation, so as to provide a film with homogeneous character thatresponds to contact with the target gas species by undergoing thedesired color change. Alternatively, the shrink-wrap film may betransparent and simply provide a shroud or envelope structure enclosingthe potential leakage site of the fluid storage and dispensing vessel,with the colorimetric member being disposed within such shroud orenvelope, to provide a visualizable color change indicative of fluidleakage, as visible through the shrink-wrap film material.

The color change may be of any suitable character providing visualevidence to a viewer that the leakage event has occurred. Accordingly,any spectral colors of the virgin or originally provided film that aredifferentiable visually from the target gas-contacted film may beutilized. Examples of colorimetric agents that may be employed in thebroad practice of the present invention include, in specificembodiments, iron oxide, copper sulfate, copper hydroxide, coppercarbonate and the like, as well as pH indicating solutions, when thefluid species in the vessel is an acid gas. For detection of hydridegases, colorimetric agents such as copper sulfate, copper hydroxide andcopper carbonate can be used. Colorimetric detection agents for fluoridegases can include iron oxide or other acid gas indicators.

As a specific example of a color-indicating shrink wrap film, the filmmay be a solvent-cast film, such as a polyvinyl alcohol (PVA) film,polyvinyl chloride (PVC) film, polycarbonate film, polyamide film, etc.,which is cast from a solution or a dispersion of the polymer resin in asuitable solvent, e.g., aqueous medium such as water, organic solventsuch as acetone, aniline, dimethyl sulfoxide (DMSO), benzene, dimethylformamide (DMF), methyl ethyl ketone (MEK), ethyl acetate, ethylenedichloride, toluene, tetrahydrofuran (THF), etc. The colorimetricchemistry can be incorporated in the solvent casting formulation, sothat the colorimetric chemistry is present as a component of the productfilm, or alternatively the film may be formed by solvent casting and thecolorimetric chemistry can be applied to the film, either as a wet filmor as a subsequently dried film, so that the colorimetric agent(s) areincorporated into the film material and therefore function thereafter tocolorimetrically indicate the presence of the target gas species towhich the film is colorimetrically sensitive.

As a further specific example, a PVA film can be cast from a solution ofPVA in diethyl ether or acetone, to which copper sulfate has been added,with such precursor solution containing 15-20% by weight of PVA, basedon the total weight of the solution, at sufficient wet film thickness toproduce a dried film of 5-6 mils thickness. The film can be cast on alow surface energy substrate, e.g., a substrate coated withpolytetrafluoroethylene, permitting the PVA film impregnated with thecopper sulfide (as a hydride gas colorimetric agent) to be peeled fromsuch substrate and thereafter used as a heat-shrink film to enshroud thefluid storage and dispensing vessel. Once the vessel, including thevalve head assembly, is fully enshrouded in the shrink-wrap film, anysubsequent leakage of hydride gas e.g., arsine, from the fluid storagevessel will change the film from bluish-white in color to black.

Alternatively, the film may be blow-molded, roto-molded, or formed inany other suitable manner.

As a further specific example, when the fluid in the fluid storage anddispensing vessel is tris(trifluoromethyl) stibine, the heat-shrink filmmay be formed of poly(vinyl pyridine), with the product film beingyellow in color. In the event of leakage from the vessel oftris(trifluoromethyl) stibine, the film changes very rapidly to a brightred color, providing a visual verification of the leakage event.

Referring now to the drawings, FIG. 1 is a front elevation view of a gasstorage and dispensing cylinder 10, including an elongate cylindricalvessel 12 whose upper portion includes a tapered neck 14 of reduceddiameter, to which is attached a valve head 16.

The valve head 16 includes a block-like valve head body 18 containinginterior gas flow passages communicating with an outlet port 20 and aburst disk 22. The valve head body 18 is operatively coupled with amanual hand wheel 24 that may be turned in respective opposingdirections, to open an interior valve element (not shown in FIG. 1) forselective dispensing of gas from the cylinder, or alternatively toterminate flow by closure of the valve in the valve block body 18.

The burst disk 22 may be constructed and arranged to release the gascontents of the cylinder in the event of fire or other catastrophiccondition resulting in over-pressure in the cylinder thatapproaches/exceeds the maximum use pressure for the cylinder.

Overlying the valve head assembly, including the valve block-associatedelements, is a valve head cover 26. The valve head cover is removablycoupled with the valve head assembly, to protect the valve head assemblyduring storage, transportation, installation and use of the cylinder.

The valve head cover 26 may as shown be provided with side openings 28therein, as conventionally employed to allow dissipation of any leakagegas, e.g., to avoid build-up of hazardous concentrations of the gas, andto facilitate blowing out the interior volume enclosed by the cover,when the leaking cylinder is isolated for quarantine, reworking ordisposal purposes.

In accordance with one embodiment of the invention, a colorimetricsheet-form element 30 is disposed on a flat surface of the valve headblock 18. Such sheet-form element 30 may for example comprise acellulosic (paper) sheet, or other mat or web element, impregnated orotherwise including the colorimetric agent that undergoes color changein exposure to the gas held in the vessel 12, in the event of a leakageoccurrence.

The openings 28 in cover 26 therefore facilitate visual inspection ofthe colorimetric element and verification of the occurrence of a leakageevent.

As an optional further feature of this embodiment of the invention, theupper portion of the cylinder 10 may be shrouded with a film 32 toenclose and overlie the upper portion of the vessel. In one specificembodiment, the film 32 is a heat-shrink film that is applied to thevessel and then subjected to appropriate heat-shrinking temperatureconditions, to cause the film 32 to conform to the exterior surfaces ofcover 26 and vessel 12, as shown. The film 32 may as illustratedenshroud the upper portion of the cylinder, terminating at a lower skirtedge 34, or alternatively the film 32 may be deployed so as to enshroudthe entire body of the cylinder 10.

It will be appreciated that by the deployment of the shrink-wrap film 32as shown in FIG. 1, a local environment is created beneath the film, inwhich any leakage gas will accumulate and serve to effect thecolorimetric change of the film.

Additionally, such arrangement will enable the film 32 to contain anyleakage of gas, so that the film thereby serves as a secondarycontainment vessel shrouding the portion of the cylinder that is mostsusceptible to leakage.

Since the film 32 is of a heat-shrink character, the lower portion ofthe film will be circumferentially in a compressive state against theexterior surface of the vessel, just below the neck and shouldersportions of the vessel, so that the skirt edge 34 provides a leak-tightsealing of the film, to prevent any egress of gas.

Accordingly, the heat shrink film may be selected to provide suitablegas permeability characteristics with respect to the contained gas, sothat diffusion through the film is precluded, or otherwise controlled ata minimal level.

As a further expedient, the film may be formed as a multi-layerlaminate, having one or more layers serving to provide diffusional andpermeation resistance to the overall film, and permitting thecolorimetric change of the film structure to be readily visuallyperceived by an observer.

Referring now to FIG. 2, there is shown a perspective view of a fluidstorage and dispensing vessel 100 according to another embodiment of theinvention.

The storage and dispensing vessel 100 comprises a cylinder 102 ofelongate character having an upper portion 105 including neck 106, and alower portion 104 having a flat bottom so that the cylinder may bereposed in vertically upstanding relationship on a support surface.

Coupled to the neck 106 of the cylinder 102 is a manual or automated (byelectrical or air means) high pressure stainless steel diaphragm valve108 comprising a valve body 110 which is secured to the neck 106 ofcylinder 102 in any suitable manner, as for example by means ofcomplimentarily matable threading on the respective engaging surfaces ofthe valve body 110 and neck 106, as augmented by threadlocking adhesive,sealant, or other medium applied to the threaded surfaces and serving toensure gas-impermeability and leak-tightness of the completed assembly.

The valve 108 comprises a manual actuator handle 114 which may bemanually rotated to open or close the valve. The valve body 110 isconnected to a discharge flange coupling 112, by means of which thestorage and dispensing vessel can be joined to suitable dispensingassembly means comprising piping, tubing, conduits, instrumentation,mass flow controllers, flow regulators of other types, purifiers,filters, etc. The valve 108 may optionally be pneumatically activatable.

The valve body 110 as shown is joined to a burst disk 122.

As illustrated, the storage and dispensing vessel 100 is fullyenshrouded by a shrink-wrap film 150, to form an enclosed interiorvolume 148 at the upper portion of the vessel, overlying the valve bodyand valve and actuator handle.

The shrink-wrap film 150 may have impregnated therein or otherwiseassociated with the film a suitable colorimetric agent that in exposureto leakage of fluid from the cylinder 102 undergoes a visuallydiscernable color change, thereby alerting the observer that a leakageevent has occurred.

FIG. 3 is a schematic cross-sectional elevation view of one gas storageand dispensing system 200 according to yet another illustrativeembodiment of the invention. The system 200 includes a fluid storage anddispensing vessel 202 of generally cylindrical form, with a cylindricalsidewall 204 closed at its lower end by floor member 206. At the upperend of the vessel is a neck 208 including a cylindrical collar 210defining and circumscribing a top opening (port) of the vessel. Thevessel wall, floor member and neck thereby enclose an interior volume228, as shown.

At the neck of the vessel, a threaded plug 212 of the valve headassembly 214 is threadably engaged with the interior threaded opening ofthe collar 210. The valve head assembly 214 includes a central fluidflow passage 220 joined in fluid flow communication with a centralworking volume cavity in the valve head assembly. The central workingvolume cavity in turn is joined to outlet 224, which may be exteriorlythreaded or otherwise constructed for attachment of a connector andassociated piping, conduit, etc. thereto.

Disposed in the central working volume cavity is a valve element 222that is joined to a hand wheel 226 in the embodiment shown, but mayalternatively be joined to an automatic valve actuator or othercontroller or actuating means.

The valve head assembly 214 also features in the valve block a fillpassage 216 communicating with fill port 218 and the interior volume 228of the vessel. The vessel 202 may thereby be charged with pressurizedgas, following which the fill port is closed and capped, as shown.

The central fluid flow passage 220 in the valve head assembly 214 isjoined at its lower end to a connector flow tube 230, which in turn isjoined to the regulator 232. The regulator is set to maintain a selectedpressure of the fluid discharged from the vessel.

At the lower end of the regulator is joined a tubular fitting 236 whichin turn is joined, e.g., by butt welding, to a filter unit 234 having adiffuser end cap 231 at its lower extremity. The filter unit may beformed of stainless steel, with the diffuser wall being formed of asintered stainless steel such as 316L stainless steel. The filter unithas a wall porosity that permits removal of all particles greater than apredetermined diameter, e.g., greater than 0.003 micrometers at 30standard liters per minute flow rate of gas from the system. Filterunits of such type are commercially available from Mott Corporation(Farmington, Conn.).

In use, a pressurized gas is contained in the interior volume 228 of thevessel 202. The gas pressure regulator 232 is set to a selected setpoint to provide flow of dispensed gas when the valve in the valve headassembly 214 is opened, with the gas flowing through the filter unit234, fitting 236, regulator 232, connector flow tube 230, central fluidflow passage 220 in the valve head assembly 214, the central workingvolume cavity, and outlet 224. The valve head assembly may be joined toother piping, conduits, flow controllers, monitoring means, etc. as maybe desirable or required in a given end use application of theinvention.

Heat-shrink film 250 is wrapped on the vessel to shroud the upperportion of the fluid storage and dispensing vessel 202. By suchshrink-wrapping, the shoulder region of vessel 202, t,he neck portion ofthe vessel and the valve head assembly are enclosed by the shrink-wrapfilm 250, in the interior volume 252 overlaid by the film.

In this embodiment, the lower portion of the shrink-wrap film 250 issealed to the exterior surface of the cylinder sidewall by a sealant256. The sealant 256 may be of any suitable type, such as a low-tackadhesive medium, caulk, putty, or other suitable medium that iseffective to leak-tightly seal the lower skirt edge portion of theheat-shrink film to the exterior side wall surface, about the fullcircumference of the vessel.

The film 250 may be impregnated or otherwise associated with or containa suitable colorimetric agent that is effective in exposure to fluidleakage from vessel 202 to undergo a color change that is visuallydiscernable by an observer.

As a further optional modification, the shrink-wrap film 250 may have onan interior surface thereof a getter material 258, for chemisorption andremoval of leakage gas from the interior volume 252 within theshrink-wrap film 250.

The getter may be of any suitable type, which is chemisorbentlyeffective for removal of the specific fluid contained in vessel 202. Byway of specific example, the getter material 258 may comprise a thinfilm of calcium, barium or magnesium, that will react with the fluid invessel 202 when same leaks into the interior volume 252, e.g., a fluidsuch as a hydride or halide gas. The getter material 258 may as shown belocalized as a discrete mass on the interior surface of the shrink-wrapfilm, or alternatively the getter may be provided as a flashed thin filmon the surface, at sufficient concentration to effectively removeleaking gas. As a still further alternative, the getter material may beprovided on an exterior surface of the neck or shoulders region of thevessel, within the interior volume 252.

The getter material 258 therefore is effective to remove the leakagegas, so that same does not pose a health or safety issue. Theshrink-wrap film 250, when a getter material is employed, can be appliedunder inert atmosphere, so as to preclude the premature reaction of thechemisorbent material with atmospheric or other ambient gases that couldotherwise deplete the capability of the getter for subsequent removal ofleaking gas from the vessel.

In use, leaking gas would therefore contact the shrink-wrap film 250,which would responsively undergo a colorimetric change visuallyperceptible to an observer, to evidence the occurrence of the leakageevent. Concurrently, the leaked gas would contact the getter material258 and be taken up, so that the vessel thereafter can be more readilyhandled for isolation, quarantine, reworking or other disposition.

With reference to the FIG. 3 embodiment, the sealant 256 is an optionalfeature, which may be superfluous if the shrink-wrap film issufficiently adherent and sufficiently shrunk to compressively self-sealat the lower skirt edge of the film. Alternatively, a tape or elasticsealing band may be employed in lieu of the sealant 256.

Although the invention has been described herein with respect toillustrative embodiments, and with reference to specific aspects andfeatures, it will be recognized that the invention is susceptible tovariations, modifications and other embodiments as will readily suggestthemselves to those of ordinary skill in the art, based on thedisclosure herein. Accordingly, the invention is intended to be broadlyinterpreted and construed, as encompassing such variations,modifications and alternative embodiments, within the spirit and scopeof the claims hereafter set forth.

1. A fluid storage and dispensing apparatus comprising a fluid storageand dispensing vessel adapted to hold a halide fluid, said vesselincluding a neck portion and a valve head assembly attached to saidvessel at said neck portion, and a colorimetric fluid leak detectiondevice, comprising a colorimetric element comprising a chemistryeffective in the presence of halide fluid to produce a color changevisually indicating a leakage event involving said halide fluid, in thepresence of atmospheric gases, said colorimetric element comprising acolorimetric material film that is clear or translucent prior to contactwith said halide fluid to facilitate visual observation of the fluidstorage and dispensing vessel underlying the colorimetric material film,said colorimetric material film defining a shroud structure that iscircumferentially sealed to an exterior surface of the vessel andoverlying the neck portion of the vessel and the valve head assembly todefine an interior void volume enclosed by the colorimetric materialfilm, wherein said enclosed interior void volume surrounds the neckportion and valve head assembly, whereby leakage of said halide fluid atsaid neck portion or at said valve head assembly can enter the enclosedinterior void volume and distribute throughout said enclosed interiorvoid volume to effect a color change in the colorimetric material filmsurrounding the neck portion and valve head assembly, thereby providinga visually perceptible response to a leakage event of said halide fluid,wherein the visually perceptible response is visible in the colorimetricmaterial film around an entire circumferential extent of the neckportion and the valve head assembly of the vessel.
 2. The fluid storageand dispensing apparatus of claim 1, wherein said colorimetric materialfilm comprises a poly(vinylpyridine) film.
 3. The fluid storage anddispensing apparatus of claim 1, wherein said fluid storage anddispensing vessel contains a halide fluid.
 4. The fluid storage anddispensing apparatus of claim 1, wherein an upper portion of the fluidstorage and dispensing vessel is wrapped in said colorimetric materialfilm.
 5. The fluid storage and dispensing apparatus of claim 1, whereinthe entire fluid storage and dispensing vessel is wrapped in saidcolorimetric material film.
 6. The fluid storage and dispensingapparatus of claim 1, wherein the colorimetric material film iseffective in the presence of a fluoride fluid to produce a color change.7. The fluid storage and dispensing apparatus of claim 1, wherein thecolorimetric material film contains iron oxide.
 8. The fluid storage anddispensing apparatus of claim 1, wherein the colorimetric material filmcomprises a polymeric film.
 9. The fluid storage and dispensingapparatus of claim 1, wherein the colorimetric material film comprises amaterial selected from the group consisting of polyethylene, polyolefin,polyvinyl chloride and polyester.
 10. The fluid storage and dispensingapparatus of claim 1, wherein the colorimetric material film comprises apolyvinyl chloride film.
 11. The fluid storage and dispensing apparatusof claim 1, wherein the fluid storage and dispensing vessel contains asemiconductor manufacturing reagent.
 12. The fluid storage anddispensing apparatus of claim 1, wherein the leak detection devicecomprises a getter within the interior void volume enclosed by thecolorimetric material film.
 13. The fluid storage and dispensingapparatus of claim 12, wherein the getter is on an interior surface ofsaid film.
 14. The fluid storage and dispensing apparatus of claim 12,wherein the getter is disposed on an exterior surface of the fluidstorage and dispensing vessel, in the interior void volume enclosed bysaid film.
 15. A method of fabricating a fluid storage and dispensingvessel adapted to hold a halide fluid, said vessel having visual leakdetection capability, wherein said vessel includes a neck portion and avalve head assembly is attached to said vessel at said neck portion,said method comprising wrapping at least a portion of said vessel with acolorimetric material film that is clear or translucent prior to contactwith said halide fluid to facilitate visual observation of the fluidstorage and dispensing vessel underlying the colorimetric material film,said colorimetric material film comprising a chemistry effective in thepresence of the halide fluid to produce a color change visuallyindicating a leakage event involving said halide fluid, in the presenceof atmospheric gases, and circumferentially sealing the colorimetricmaterial film to an exterior surface of the vessel so that thecolorimetric material film overlies the neck portion of the vessel andthe valve head assembly to define an interior void volume enclosed bythe colorimetric material, with the colorimetric material defining ashroud structure circumferentially surrounding the neck portion andvalve head assembly, whereby leakage of said halide fluid at said neckportion or at said valve head assembly can enter the enclosed interiorvoid volume and distribute throughout said enclosed interior void volumeto effect a color change in the colorimetric material surrounding theneck portion and valve head assembly, thereby providing a visuallyperceptible indication of a leakage event of said halide fluid, whereinthe visually perceptible indication is visible in the colorimetricmaterial film around an entire circumferential extent of the neckportion and the valve head assembly of the vessel.
 16. The method ofclaim 15, wherein said colorimetric material film comprises apoly(vinylpyridine) film.
 17. The method of claim 15, wherein said fluidstorage and dispensing vessel contains a semiconductor manufacturingreagent.
 18. The method of claim 15, wherein an upper portion of thefluid storage and dispensing vessel is wrapped in the colorimetricmaterial film.
 19. The method of claim 15, wherein the entire fluidstorage and dispensing vessel is wrapped in the colorimetric materialfilm.
 20. The method of claim 15, wherein the fluid storage anddispensing vessel contains a fluoride fluid.
 21. The method of claim 15,wherein the fluid storage and dispensing vessel contains anorganometallic compound.
 22. The method of claim 19, wherein thecolorimetric material film contains iron oxide.
 23. The method of claim15, wherein the colorimetric material film comprises a polymeric film.24. The method of claim 15, wherein said colorimetric material filmcomprises a material selected from the group consisting of polyethylene,polyolefin, polyvinyl chloride and polyester.
 25. The method of claim15, wherein the colorimetric material film comprises a polyvinylchloride film.